The HDP versions are not listed while setting up the cluster using Ambari 188.8.131.52 on Ubuntu 16.04. All prerequisites have been done on the machine.
Looks like the repo_version table of ambariDB is somehow empty or not populated.
As you are trying to create a fresh cluster hence it will be quick to try the following to reset the ambari DB and thencheck again.
# ambari-server stop
# ambari-server reset
# ambari-server start
The Ambari DB will be reset to default in this case.
You can also take a backup of the ambari DB becore doing the above just incase if you have added any information to the ambari DB like installed any blueprint ..etc.